The Energy Department recently released the 2014 Hydropower Market Report, the first report to quantify the size, scope, variability, and vast potential of the largest source of renewable power in the nation.

Today, hydropower remains the most common and least expensive source of renewable electricity in the United States. See how hydropower in our country has evolved over the last 100 years with the Energy Department's new interactive timeline.

Ninety-two teams from industry and academia are moving toward the first milestone of the Wave Energy Prize to double the energy captured from ocean waves and win a prize purse totaling over $2 million.